Power!

[Leo Stolenberg]

Hi! Well, this is a pretty interesting solution, I have a similar situation

[LClark007]

Thanks for such good information. I'd considered that a solar panel trickle charges the main batteries, I wonder if it could be used to charge a portable battery pack in the same way. I need this for my work. I reckon a decent jump pack would do you. If I am a technician, all my tools are in my car all the time and I have everything when someone calls me. I had an old solar generation that helped to get rid of some troubles for many years and now I want to buy a new one. I hope that I helped you.

[budweiser]

it is very good, i was thinking to do something similar on the 3l

[AlexKzn130]

Okay fellas, for those interested in maybe sorting out a similar solar setup, after exhaustive research this is how I'll be doing mine:

Power calculations...


Smartphone

2600mAh battery, 5v charge = 13wh

Tablet

4450mAh, 5v charge = 22wh

Bluetooth speaker

2200mAh, 3.6v charge = 8wh

LED light

18w (for four hours of use) = 72wh

So...

Scenario a) Total charging phone / light / speaker = 93wh

Scenario b) Total charging tablet / light / speaker = 102wh

Scenario c) Total charging phone / tablet / light / speaker = 115wh

Considering I'll probably be using the solar panel for camping mainly in three seasons (March - October) and mainly in West Wales, the irradiance figures for Swansea (for a 100w solar panel operating at 75% efficiency to account for losses in the system and capture process) are:

February - 100kWh/Sq m
March - 166
April - 264
May - 342
June - 356
July - 353
August - 298
September - 203
October - 116

With these as an average then, a 100w panel should be able to provide enough power for all my items in 8 of 9 months, and enough for lighting, speaker and phone or tablet for February.

November, December and January provide 67, 44 and 54kWh/Sq m respectively, which is still enough for a couple of hours of lighting and a fully charged phone.

The above is also calculated for 'worst case', i.e. in powering each item to full charge each day. Realistically the only thing needing daily charge would be the light, the other items could be charged every other day, as they are each supposed to last at least 10 hours once charged.

I've also measured the roof space behind my roofrack, which is 100cm x 80cm. A 100W panel fits perfectly in this space, and I'll fit it on a hinge and catch to angle it perpendicularly to the sun ray angle when in camp. I could now go on about MPPT controllers but I'll leave it at that.

Hope this helps someone!
Owen

Wow it's a lot more thorough than wat I figured out, well done mate, I'll use ur post as a point of reference

[budweiser]

use wind power, forget the solar panels

[pyemaster]

Okay fellas, for those interested in maybe sorting out a similar solar setup, after exhaustive research this is how I'll be doing mine:

Power calculations...


Smartphone

2600mAh battery, 5v charge = 13wh

Tablet

4450mAh, 5v charge = 22wh

Bluetooth speaker

2200mAh, 3.6v charge = 8wh

LED light

18w (for four hours of use) = 72wh

So...

Scenario a) Total charging phone / light / speaker = 93wh

Scenario b) Total charging tablet / light / speaker = 102wh

Scenario c) Total charging phone / tablet / light / speaker = 115wh

Considering I'll probably be using the solar panel for camping mainly in three seasons (March - October) and mainly in West Wales, the irradiance figures for Swansea (for a 100w solar panel operating at 75% efficiency to account for losses in the system and capture process) are:

February - 100kWh/Sq m
March - 166
April - 264
May - 342
June - 356
July - 353
August - 298
September - 203
October - 116

With these as an average then, a 100w panel should be able to provide enough power for all my items in 8 of 9 months, and enough for lighting, speaker and phone or tablet for February.

November, December and January provide 67, 44 and 54kWh/Sq m respectively, which is still enough for a couple of hours of lighting and a fully charged phone.

The above is also calculated for 'worst case', i.e. in powering each item to full charge each day. Realistically the only thing needing daily charge would be the light, the other items could be charged every other day, as they are each supposed to last at least 10 hours once charged.

I've also measured the roof space behind my roofrack, which is 100cm x 80cm. A 100W panel fits perfectly in this space, and I'll fit it on a hinge and catch to angle it perpendicularly to the sun ray angle when in camp. I could now go on about MPPT controllers but I'll leave it at that.

Hope this helps someone!
Owen

[pyemaster]

That's brilliant!

So, if a tablet/phone draws 2 amps, two 20W LED lights 4 amps and a portable speaker 1 amp (7 amps in total), this total multiplied by 12V (because it's a 12V battery) equals 84W. This, multiplied by 6 hours (maximum time used per evening) amounts to 504 watt hours?

So this would take a 120w solar panel 4.2 hours to charge this amount? Can it be as simple as that or am I totally way out / missing something

Owen

[Growler]

Likewise! Thanks for the link, watts are beyond my limits of comprehension right now, I'm only just remembering amps!

I've been thinking I needed to work out amp draw to calculate amp hours?! This is bloody confusing...

Owen

try THIS

[pyemaster]

Likewise! Thanks for the link, watts are beyond my limits of comprehension right now, I'm only just remembering amps!

I've been thinking I needed to work out amp draw to calculate amp hours?! This is bloody confusing...

Owen

[tashtego]

Check this.

https://www.windynation.com/jzv/inf/...Power%20System

I looked at it when researching solar panels for charging mobiles etc. You need to convert your amp requirements into Watts. The amount of sunlight reaching the surface of the Earth is about 300 Watts per square meter, roughly...unless you leave in Scotland...

Better get the calculator out. How is your GCSE Physics? Mine is terrible, forgotten everything!

Cheers

[pyemaster]

I should really add that I'd be looking to recoup those amp hours over the course of one average day of light in Britain.

Owen

[pyemaster]

Quick update!

To recoup circa 40amp hours by solar, does anyone know what size panel I'd need?

Owen

[pyemaster]

Okay, so, the plan then is to get a decent dual purpose leisure battery to:

A) provide power for everyday camping in the evening (LED lighting, music and charging phone/tablet).

B) be used to start the truck should the main batteries ever go flat (they shouldn't).

My plan then is to charge the leisure battery each day through either a roof-mounted solar panel (if stationary on site), or a smart charger working through an inverter off the cigarette lighter (if driving during the day).

My issue is I have no idea how much my expected usage will take out of the battery each evening...

The 3 things it will be doing:

- Powering two of these for lighting (though they'll be on a dimmer switch, if that makes any difference??): https://www.amazon.co.uk/gp/aw/d/B01...=AVEFNIEDS5OE4

- Charging a portable Bluetooth speaker

- Charging a smartphone / tablet.

So (thanks for getting this far!) with the above needing a few hours of charge from the leisure battery each evening, how much energy will they collectively use, and with that in mind, what size leisure battery would I need?

Thanks guys!

Owen

[AlexKzn130]

Hmm, food for thought chaps.

So maybe instead of the jump pack, getting a decent deep cycle leisure battery, and trickle charging it from a roof-mounted solar panel?

That way the truck's (starting) batteries are left well alone, and lighting for camp, phone charging and music can all come off the leisure battery in the evening. Plugging it into the solar panel over the next day will then have it ready again for use the next night?

If it was fully charged I take it it could be used to jump start a flat battery too?

Owen

Thats how im planning to do it yes

[pyemaster]

Right so a little further research later...

Thinking of one of these - https://www.tayna.co.uk/Numax-CXV31MF-P3694.html

Trickle charged off a roof mounted solar panel like the one Alex linked to above. I now just need to get my head around how they'd connect up, and what benefits a 'solar charger' offers.

The Numax leisure battery above seems fine for my light camping use (nightly lighting, music and charging a phone/tablet), but also with 1000 CCA has enough grunt to be used as a jump battery if needed in an emergency.

Owen